Device for locking a cutting plate on the body of a toolholder

ABSTRACT

This invention relates to a device for locking a cutting plate with its support plate on the body of a toolholder comprising a screw which passes through the cutting plate and the support plate before being screwed into the body of the toolholder, wherein the body of the toolholder has a tapped housing receiving an externally threaded sleeve, said sleeve itself having a tapped housing intended for receiving the screw.

United States Patent Viellet [54] DEVICE FOR LOCKING A CUTTING [4 Mar,14, 1972 [56] References Cited UNITED STATES PATENTS 2,598,581 5/1952McKenna ..29/96 3,354,526 11/1967 Erkfritz ....29/96 2,887,760 5/1959Armstrong... ....29/96 3,059,316 10/1962 Bader ....29/96 3,289,272 12/1966 Stier ....29l96 2,877,535 3/1959 Williams ..29/96 PrimaryExaminer-Harrison L. Hinson Attorney-Marn & Jangarathis [S 7] ABSTRACTThis invention relates to a device for locking a cutting plate with itssupport plate on the body of a toolholder comprising a screw whichpasses through the cutting plate and the support plate before beingscrewed into the body of the toolholder,

wherein the body of the toolholder has a tapped housing receiving anexternally threaded sleeve, said sleeve itself having a tapped housingintended for receiving the screw.

2 Claims, 1 Drawing Figure \A L A A PAIENTEBMARM I972 3, 648,341

Inventor Attorney DEVICE FOR LOCKING A CUTTING PLATE ON THE BODY OF ATOOLHOLDER The present invention relates to a device for locking acutting plate on the body of a toolholder.

Devices are already known for locking a cutting plate on the body of atoolholder by means of a conical headed screw bearing on the cuttingplate, the screw screwing into the body of the toolholder. Such deviceshave the disadvantage of being difficult to unlock when the cuttingplate is to be replaced, due to the grip of the head of the screw on theplate consecutive to the heat produced by the cutting plate inoperation. This results in a loss of time upon every dismantling.

The present invention has for its object to remedy this disadvantage byimproving the device for locking a cutting plate on the toolholder. Theplate is still locked by a central screw, but said latter is screwedinto a sleeve itself screwed into the tapped hole of the toolholder.

The invention will be described in greater detail with reference to theaccompanying drawings, in which:

the single FIGURE shows a partially cutaway longitudinal section throughthe device for locking a cutting plate on the body of a toolholder,according to the invention.

The body of the toolholder] has at one of its ends a disengagement 2,the shape of which corresponds to that of the plate 10. A tapped hole 3is pierced in the toolholder, substantially in the center of thedisengagement and over the whole thickness of the toolholder.

A cylindrical sleeve 4 pierced with a tapped hole 5 is screwed insidethe hole 3.

A support plate 6 is placed on the upper part of the toolholder and inthe center of disengagement 2. Said support plate is perforated with acentral hole whose upper aperture comprises a chamfer 7. Said supportplate is locked in its housing by a resilient split ring 8 whose uppersides 9 are widened out and abut on the chamfer 7. The lower cylindricalpart of the resilient split ring is forcibly fitted on the threads ofthe tapped hole 3 of the toolholder.

The cutting plate 10 comprising a smooth central hole with a chamfer lllbordering the upper aperture is placed on the support plate.

The whole of the device is held in locked position by a central conicalheaded screw 12 which passes through the cutting plate, the supportplate and the split ring 8 in order to be screwed inside the sleeve 4.

The piercing of the cutting plate is slightly shifted with respect tothe axis of the screw in order that, in locking position of the cuttingplate, the conical head of the central screw exerts a pressure directedtowards the mass of the body of the toolholder, that is to say towardsthe right in the example shown.

The lower end of the sleeve 4, opposite the cutting plate, has afastening member that is sunk or raised or is otherwise arranged so asto permit its maneuver.

In the example shown, the central screw is locked by a socket screwhexagon wrench 13 which is inserted into the housing provided in thecenter of the conical head 12. When the tool has been in operation andthe screw and plate are hot, unlocking is efiected by lifting the sleeve4 by means of a second socket screw hexagon wrench 114 which is insertedin the housing provided at the end of the sleeve; the screw may then beunscrewed very easily.

The details of the embodiment described may be modified withoutdeparting from the scope of the invention.

What I claim is:

l. A cutting tool comprised of a toolholder having a cutting platereceiving area, an access area opposite said receiving area and athreaded aperture extending through said toolholder between saidreceiving area and said access area;

a sleeve threaded into said aperture having a threaded aperture thereinand provided with means to turn said sleeve from the access area side ofsaid toolholder to cause said sleeve to advance therethrough towardssaid receiving area" a cuttihg plate including a tapered aperturepositioned on said cutting plate receiving area; and

a conically headed screw positioned trough the tapered aperture of saidcutting plate and threadably engaged with the threaded aperture of saidsleeve to lock said cutting tool on said tool holder.

2. The cutting tool as defined in claim ll including a support platedisposed between said cutting plate and said toolholder and including atapered aperture for receiving a tapered split ring which engages thetapered aperture of said support plate and which engages forcibly thethreaded aperture of said toolholder.

1. A cutting tool comprised of a toolholder having a cutting platereceiving area, an access area opposite said receiving area and athreaded aperture extending through said toolholder between saidreceiving area and said access area; a sleeve threaded into saidaperture having a threaded aperture therein and provided with means toturn said sleeve from the access area side of said toolholder to causesaid sleeve to advance therethrough towards said receiving area; acutting plate including a tapered aperture positioned on said cuttingplate receiving area; and a conically headed screw positioned throughthe tapered aperture of said cutting plate and threadably engaged withthe threaded aperture of said sleeve to lock said cutting tool on saidtool holder.
 2. The cutting tool as defined in claim 1 including asupport plate disposed between said cutting plate and said toolholderand including a tapered aperture for receiving a tapered split ringwhich engages the tapered aperture of said support plate and whichengages forcibly the threaded aperture of said toolholder.